Rocket carrying cargo to space station set to launch Tuesday night

A package of supplies and fresh new science experiments is set to be launched Tuesday at 11:05 p.m. Eastern time to the International Space Station (ISS) aboard the Atlas V rocket.

The 188-foot rocket, operated by a joint venture between Lockheed Martin and Boeing, called United Space Alliance, will blast off from Cape Canaveral Air Force Station in Florida, and spend three days traveling to the space station, where six American and Russian astronauts are living and working. The launch will be broadcast live on NASA TV starting at 10 p.m.

Atlas will carry on its tip a nearly 4-ton package of clothes, food, technologies, and scientific instruments, all inside a pressurized spacecraft called Cygnus, built and operated by Dulles, Va.-based Orbital ATK. Also onboard will be scientific experiments from government and commercial researchers who want to take advantage of a zero-gravity environment to test new adhesives, observe behavior of soil, measure the chemical composition of meteors entering Earth's atmosphere, and study how fire spreads in space.

"It's like Christmas when a supply craft arrives," Dan Tani, a former astronaut who now is senior director of mission cargo and operations for Orbital, said in a NASA announcement. "It's always fun to watch another vehicle approach, and then it’s like opening a box of goodies and finding some stuff you've been wanting and some surprises you didn't know about," he said.

The Cygnus delivery is one of 10 packages that NASA has paid Orbital $2.6 billion to deliver to the space station through 2018. Since the end of the NASA’s Space Shuttle program in 2011, Orbital and Hawthorne, Calif.-based SpaceX have been delivering American cargo to the ISS, mostly without a hitch.

The year 2014, though, ushered in some setbacks for commercial, unmanned spaceflight. In October, Orbital’s rocket Antares, with Cygnus and ISS supplies onboard, exploded seconds after liftoff. A few months later, in April 2015, the Russian space agency lost control of a rocket carrying supplies to the space station. It ultimately burned up in the atmosphere without reaching the lab. And then in June, SpaceX’s supply-carrying rocket, Falcon 9, disintegrated minutes after liftoff. The string of incidents left ISS astronauts without new supplies for a year, until a December 2015 launch of Cygnus on the Atlas V rocket.

“This is a risky business we’re in,” says Frank Demauro, a director at Orbital, in an interview with The Christian Science Monitor.  “Failures do occur and they’re extremely unfortunate,” he says.

The problem in the failed Orbital launch in 2014 was a faulty engine, says Mr. Demauro. The company has replaced it and is in the process of building two rockets with new engines. Orbital will start testing the new engines in early May, and says it will be ready to launch another supply package to the space station this summer.

“We are very confident that the process we’re using to validate the design work and the assembly work is rigorous and tested,” Demauro said.

Tuesday’s Cygnus launch is the first of several resupply missions scheduled over the next few weeks, reports Florida Today. The Russian space program will deliver cargo to the ISS next, followed by SpaceX.

After it arrives in a few days, the Cygnus will stay attached to the space station for two months. Astronauts will unload the cargo and refill the spacecraft with their garbage before releasing it from the station. It will travel away from the ISS and burn up when it reaches the Earth’s atmosphere, with the remains falling into the Pacific Ocean.